Display control apparatus employing bit map method
US4837564A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 1986 |
| Grant date | Jun 6, 1989 |
| Priority date | — |
| Expiry date | Nov 7, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G5/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A display control apparatus using a bit map method, for controlling character attribute data, such as an underline and an overline. In the apparatus, a line control memory is arranged to preset information of character attributes in units of lines of character fonts to be transferred to a video memory; in a DMA transfer sequence of a DMA transfer controller. Character attribute control is performed in a character controller for each line transfer according to the attribute information read out from the line control memory, and expansion of a character font from a character font memory area to the video memory can be simultaneously performed with processing of character attributes from the line control memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.